Abstract: An object of the invention is to provide an image forming apparatus in which a unit can be attached to the apparatus body in a status where a correct positional correlation between a photoconductive drum and each of other process devices mounted on a unit is maintained. A photoconductive drum is positioned within a copier body by a rotating drive shaft, and the other process devices mounted on a process unit are positioned within a copier body by a boss and a locking member. The boss positions the rotating drive shaft within the copier body. Since the locking member is fitted onto a front-side end of the rotation drive shaft, the locking member is positioned within the copier body by the rotating drive shaft. The other process devices mounted on the process unit are positioned within the copier body by the rotating drive shaft via the boss and the locking member.

Abstract: An image forming apparatus provided with a photoreceptor with an internal gear includes the internal gear in a photoreceptor drum, a pinion gear in engagement with the internal gear, and a cleaning unit and a developer unit which apply contact pressure onto the photoreceptor drum. The pinion gear is provided in such an area that a resulting force of the contact pressure respectively applied from the process elements does not cause a distortion of the photoreceptor drum which exceeds an axial backlash determined in initialization according to a distance between axes of the pinion gear and the internal gear. The described arrangement prevents interference between non-driving surfaces of the internal gear and the pinion gear. As a result, a smooth rotary motion of the photoreceptor drum can be ensured, thereby preventing an image defect caused by an unstable rotary motion of the photoreceptor drum.

Abstract: A scroll compressor has an Oldhams ring made of sintered metal operating as a rotation-prevention mechanism for holding the rotation scroll. The Oldhams ring is formed to a size to accommodate the cutting work or the grinding work of the surface processing during the forming of the sintered metal, and, as a result, the productivity of the Oldhams ring can be improved and the wear resistance becomes excellent. A scroll compressor that is inexpensive and has a high reliability may be made of a hard sintered metal which has an excellent wear resistance. A first groove 3a and the second groove 3b are formed in the end face 3 of the ring 2 of the Oldhams ring into the sintered metal. And, after the processing, the first groove 3a is deepest, and the depth is progressively reduced in order of the second groove 3b and the end face 3 in the Oldhams ring. The wear on the corner part of the tool, which is easiest to wear being used to process the side face of the keys is reduced due to the presence of these grooves.

Abstract: In this digital color copier, laser beam scanner units of the same configuration are arranged in parallel with each other, and all are controlled in a unified manner by a laser control unit provided outside the units. In order to synchronously rotate the polygon mirrors in a precise manner, the speeds of rotations of their motors, fed back from tacho-generators are compared to the reference frequency generated from an oscillator so as to allow a motor control circuit to control the driving motors of the polygon mirrors. Further, the BD signals from beam detectors (BD) are fed back to the laser control unit so that all the BD signals from the laser scanner units for black and the three colors can become synchronized with each other, thus enabling control of the polygon mirrors.

Abstract: In a paper-punching device for use in an image-forming apparatus, the rear edge of a sheet of paper that is being transported through a transport guide is detected by the photosensor. After a predetermined time has passed since the detection, a punching device is activated. At this time, a punching member is depressed downward, and a punching blade attached to its top penetrates through the sheet of paper, thereby forming a punch hole. Even during the punching operation, transport rollers continue to rotate. Therefore, when the sheet of paper is caught by the punching blade, the transport rollers are allowed to slip predetermined amount with respect to the paper. For this reason, at least one of the transport rollers is made of a foamed material. With this arrangement, since the punching operation is carried out on the rear side of the sheet of paper, it becomes possible to reduce the occurrence of paper jams even if sheets of paper are transported in succession.

Abstract: An image forming apparatus provided with a photoreceptor with an internal gear includes the internal gear in a photoreceptor drum, a pinion gear in engagement with the internal gear, and a cleaning unit and a developer unit which apply contact pressure onto the photoreceptor drum. The pinion gear is provided in such an area that a resulting force of the contact pressure respectively applied from the process elements does not cause a distortion of the photoreceptor drum which exceeds an axial backlash determined in initialization according to a distance between axes of the pinion gear and the internal gear. The described arrangement prevents interference between non-driving surfaces of the internal gear and the pinion gear. As a result, a smooth rotary motion of the photoreceptor drum can be ensured, thereby preventing an image defect caused by an unstable rotary motion of the photoreceptor drum.

Abstract: A toner replenishing device has a hopper for storing toner. The hopper has an L-shaped so as to have a large volume in a lateral direction, thereby ensuring that the hopper has the volume corresponding to several toner containers. The toner stored in a lower portion of the hopper is transported by toner transport devices to the vicinity of a toner supply opening provided on the tip of the hopper. The remaining amount of toner is detected by sensors that detect the amount of toner remaining in the toner replenishing device step-by-step. This results in a toner replenishing device having a large toner storage section (1) in which the aggregation of toner due to dead weight can be prevented and (2) in which the amount of toner remaining can be displayed step-by-step and the supply of toner can be carried out in advance before a shortage of toner occurs.

Abstract: A charging device which can suppress elevation of the grid plate under tension is obtained. In the charging device, elevation suppression means is provided at the opposing ends of the regulation member for regulating the distance between the surface of the photoreceptor and the grid plate. By the elevation suppression means, the breadthwise outer edge portions of the plate are forced to bend up toward the photoreceptor and the central portion thereof deflects in the opposite direction toward the regulation member and is brought into close contact therewith, so that grid plate is kept flat on a level with the regulation member.

Abstract: In a paper-punching device for use in an image-forming apparatus, the rear edge of a sheet of paper that is being transported through a transport guide is detected by the photosensor. After a predetermined time has passed since the detection, a punching device is activated. At this time, a punching member is depressed downward, and a punching blade attached to its top penetrates through the sheet of paper, thereby forming a punch hole. Even during the punching operation, transport rollers continue to rotate. Therefore, when the sheet of paper is caught by the punching blade, the transport rollers are allowed to slip a predetermined amount with respect to the paper. For this reason, at least one of the transport rollers is made of a foamed material. With this arrangement, since the punching operation is carried out on the rear side of the sheet of paper, it becomes possible to reduce the occurrence of paper jams even if sheets of paper are transported in succession.

Abstract: A photoreceptor drum driving mechanism includes a drum drive gear provided at a leading end of a drive shaft, which is in mesh with an internal gear mounted to a photoreceptor drum and a roller coaxially formed with the drive shaft. The mechanism further includes a circular arc surface in contact with the roller in a deflecting direction of the drive shaft. As a result, the drive shaft of the drum drive gear can be prevented from being deformed in a pressure angle direction of the drum drive gear. As this eliminates irregularities in rotations of the photoreceptor drum, a distortion of an image in an image forming process or in a transferring process can be prevented.

Abstract: A developing unit includes a developing tank and a toner hopper. The developing tank is disposed to oppose a recording medium rotatably mounted to an image forming apparatus utilizing electrophotography. A developing member conveys a developer and attaches toner to an electrostatic latent image formed on the recording medium to develop the electrostatic latent image. The toner hopper has a toner supply port for supplying toner to the developing tank through a toner replenishing port formed in the developing tank. The developing tank is detachable in a direction of a rotating shaft of the recording medium, and is movable in a direction perpendicular to the direction of the rotating shaft of the recording medium so as to separate from or oppose the recording medium. The toner hopper has a shutter for opening/closing an opening of the toner supply port.

Abstract: Disclosed is a method of working a semi-finished scroll member for a scroll compressor which has a circular end plate having a first end face and a second end face with a spiral wrap extending therefrom. Before the second end face and the wrap are machined, the outer peripheral surface of the end plate is formed therein with a circumferencial groove to provide jaw finger engaging surfaces spaced from the first and second end faces of the end plate. Then, radial grooves are formed in the outer periphery of the end plate such that each groove extends between and is open in one of the jaw finger engaging surfaces and in the first end face of the end plate. Thereafter, the semi-finished scroll member is positioned relative to a machine tool such that the first axial end face of the end plate is placed adjacent a back-up member of the machine tool.

Abstract: A closed type motor-driven compressor includes a motor accommodated in a closed container and a compression mechanism connected through a crank shaft to the motor. A shielding member having a cylindrical portion substantially concentric with the axis of the compression mechanism is disposed between the motor and the compression mechanism. This shielding member defines a shielding air space between the motor and the compression mechanism for preventing a permeation of a lubricating oil. An inlet of a discharge pipe of the closed type motor-driven compressor is positioned inwardly of this shielding air space.

Abstract: A magnetic head has a magnetic core comprising a first half core on which a thin magnetic metal film is deposited and a second half core which is opposed to the first half core across a magnetic gap. The film thickness of the thin magnetic metal film of the first half core continuously varies at about a constant rate within a portion thereof adjacent to the effective portion of the magnetic gap.

Abstract: A sealing material for sealing electronic parts is composed of a low-melting-point glass and a filler which has its surface modified by coating with ZnO and is compatible with low melting point glass.

Abstract: A paper supply apparatus having a main recording paper stacking table having its front end disposed below a paper pressing portion of the paper supply roller, and an auxiliary recording paper stacking table disposed above the main recording paper stacking table. The front end of the main recording paper stacking table is urged toward the paper pressing portion of the paper supply roller or away from the paper pressing portion of the paper supply roller by an oscillation device for oscillating the main recording paper stacking table.

Abstract: A magnetic head including pair of core halves joined opposite to each other, each core half including a first magnetic material on which is deposited a magnetic film of a second magnetic material having a high saturation magnetic flux density and a low magnetic permeability compared with the first magnetic material, both the magnetic films having a magnetic gap arranged therebeteween, includes a pair of nonmagnetic members, each of which is adjacent to each end of the magnetic gap, in a surface of the head, along which a recording medium slides, wherein each of the magnetic films extends along the outer edge of the nonmagnetic member adjacent to one of the core halves, and the boundary between the first magnetic material and the second magnetic material includes a portion extending outward and a portion extending parallel to the magnetic gap and out of alignment with the first-mentioned portion.

Abstract: A magnetic head is disclosed. The magnetic head has a block which is formed of a first magnetic material in which a groove for a winding is formed, a first magnetic film which is deposited on a surface of the block in which the groove is formed and is formed of a second magnetic material having a higher saturation magnetic flux density than that of the first magnetic material, a nonmagnetic film which is formed on the first magnetic film and serves as a magnetic gap, a second magnetic film which is deposited on the nonmagnetic film and is formed of the second magnetic material, and a reinforcing block. A portion of the reinforcing block on the side of a magnetic recording medium slide surface is formed of a nonmagnetic material, and the other portion is formed of a magnetic material. A magnetic material-side boundary portion between the nonmagnetic and magnetic materials is inclined to form an acute angle with the nonmagnetic film.

Abstract: A magnetic head in which a first magnetic film made of a material of high saturation magnetic flux density is deposited on the surface of a block made of a high permeability material and which contains a groove for winding. A nonmagnetic film made of a nonmagnetic material and serving as a magnetic gap is formed on the first magnetic film; and a second magnetic film made of a material of high saturation magnetic flux density is further formed on the nonmagnetic film. A reinforcing block is arranged on the second magnetic film and has a nonmagnetic material portion exposed to a slide surface of a recording medium. The high permeability material block, the first magnetic film and the second magnetic film together constitute a magnetic core, and the second magnetic film is bonded with the reinforcing block.

Abstract: A sealing glass composition suitable for sealing members in semiconductor devices at a temperature below about 450.degree. C. and a comparatively low thermal expansion coefficient of about 35-50.times.10.sup.-7 /.degree.C. matching that of semiconductors. The sealing glass composition comprises 50-80 vol % solder glass powder and 20-50 vol % filler powder of a ceramic comprising, by weight, PbO 65-75%, TiO.sub.2 10-25%, Fe.sub.2 O.sub.3 1-10%, WO.sub.3 1-12%, and CaO 0-5%, so that Ti in the PbTiO.sub.3 filler is partially substituted by Fe and W. The filler powder has an average particle size of about 5 .mu.m. In use of the sealing glass composition, microcracks are absent in glass phase around the filler after sealing.